Add a single VSA user to the AuthAnvil > Two Factor Auth > Agent Procedure Approval page. This VSA user must be configured to use 2FA to log into the VSA.
Check the AuthAnvil user (or grouped user) that will be used for approval requests checkbox.
The VSA user specified in step 1 creates a new agent procedure or saves an existing agent procedure using the Agent Procedures > Schedule / Create page.
The same VSA user then clicks the Agent Procedures > Schedule / Create > Approve using AuthAnvil button to enter his or her 2FA passcode to approve the agent procedure.